The present invention relates to a process for preparing a spherically shaped microcomposite comprising a perfluorinated ion-exchange polymer containing pendant sulfonic acid groups and/or pendant carboxylic acid groups entrapped within and highly dispersed throughout an inorganic oxide network. Due to their high surface area and acid functionality, these spherically shaped microcomposites possess wide utility as improved solid acid catalysts.
A microcomposite comprising perfluorinated ion-exchange polymers containing pendant sulfonic acid groups and/or pendant carboxylic acid groups entrapped within and highly dispersed throughout a metal oxide network and its preparation are disclosed in WO95/19222. The microcomposites described therein are irregular shaped particles which can be subject to attrition. Attrition can lead to fines which can cause problems in certain filtering processes and columns, such as clogging, pressure build up and the generation of friction. Fines can also find their way into a final product in certain applications which is undesirable.
Canadian Patent Application No. 2,103,653 describes shaped organosiloxane polycondensates in the form of macroscopic spherical particles. The polycondensates described contain no perfluorinated ion exchange polymer.
It is an object of the present invention to provide a shaped microcomposite that possesses high catalytic activity, high attrition resistance, and better handling characteristics.